Powering circuit with alternative and/or concurrent power sources

control systempower supplyprotectionstability

I have one of these led projectors which is normally powered by the embedded motion sensor.

I want to be able to power it manually by a switch button. I need to do this in both alternative and concurrent mode. By alternative I mean that the projector is turned on either by the motion sensor or manually by myself; by concurrent I mean that it is turned on by both at the same time.

In order to achieve this I can follow two these strategies:

  1. simulate a motion detection by providing the control circuit with the same signal provided by the motion sensor;
  2. power the projector directly.

I have opened the device and have found out the following:

  • the projector is powered by a 22-25VDC power supply provided by the control circuit.
  • out of the motion sensor come out three wires which are fed into the control circuit. I have yet to investigate what do each of this does.

In both cases the difficulty I have is protecting the existing circuit from voltages and currents generated by the power I supply myself. I think this could easily happen in the concurrent mode.

How do I deal with these two inputs?

Best Answer

By fiddling around with the device I found out the projectors are turned on when power is first supplied to them. Therefore a switch relay did the trick.

A big thank you to the community for your support!

Related Topic